


Reasoning

by ClockworkSampi



Category: Undertale (Video Game)
Genre: Alternate Universe - Human, Alternate Universe - Modern Setting, Gen
Language: English
Status: Completed
Published: 2015-12-21
Updated: 2015-12-21
Packaged: 2018-05-08 05:37:54
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,857
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5485583
Author URL: https://archiveofourown.org/users/ClockworkSampi/pseuds/ClockworkSampi
Summary: <blockquote class="userstuff">
              <p>“How would you like to come over for dinner on Saturday?”</p>
<p>Sans had three very good, mediocre reasons, that both he and Toriel knew, as to why he could never say, 'sure.'</p>
<p>“Sure,” he said.</p>
            </blockquote>





	Reasoning

**Author's Note:**

> Wherein I utilize several alternate universes for the purposes of:  
> A) Shaking off some rust  
> B) Tinkering with some more esoteric characterizations I would not have the chance to in regular cannon  
> C) Having fun with some headcannons I have  
> This work of fanfiction contains human and modern setting AUs, as indicated by the tags, but there is also a secret twist AU. See if you can figure out what it is!

Sans hadn’t really wanted to come.

 

Nothing against Toriel, but the phrases, ‘hey, you wanna go grab a bit to eat,’ spoken at three in the morning, and, ‘would you like to come over for dinner on Saturday,’ spoken on a Wednesday during off hours, had different connotations. He had little experience with the latter, but it probably involved something more than a hoodie and slippers to go to, and he wasn’t entirely comfortable with that caveat.

 

That was the third reason Sans hadn’t wanted to come.

 

But at the same time, he didn’t, well, he _didn’t_ have anything against Toriel. He liked her. They laughed at each other’s jokes, they shared recipes, they sent poorly worded texts to each other so late into the night that it became early. She had been his best friend for as long he could remember.

 

He still felt a little guilty about how immediately he regretted saying, “Sure,” as he pulled up to Toriel’s place a few days later.

 

Sans had barely knocked before Toriel opened the door, beaming like the sunshine. His untied sneakers had hardly finished being ushered in before she sang out:

 

“Chara! Frisk! There is someone I would like you to meet!”

 

Ah, yes. The children Toriel had adopted a while back, apparently lifting them out of some troubled times.

 

Nice kids, Toriel had nothing but good words to say about them. Twins, but different as can be.

 

Frisk was sister. Chara was brother.

 

Frisk was quiet as a mouse. Chara was very adamant on letting everyone know he had an opinion.

 

Frisk always had her head between books. Chara preferred video games; horrible ones, Toriel always bemoaned, involving gross misuse of gas-powered lumbering equipment.

 

When they would go to MTT Burger Emporium, Frisk sometimes had trouble putting down one Glamburger. Whereas Chara regularly wolfed two Legendary Heroes.

 

Two figures emerged from a scamper down a hall. If Sans were inclined to guess, based on the copious amounts Toriel had told him, the one in green and yellow was Chara and the one in purple and blue was Frisk.

 

Chara smiled massively at Sans, but the child’s eyes, red like a bleeding sunset, held a look that Sans would not immediately associate with one so young, or sane.

 

Frisk, to his hushed surprise, didn’t give Sans much an appraisal at all. Assumedly, because of the red and white cane she dragged in front of her.

 

Sans heard the door shut, the lock click, and his heart catch for a beat. That was it, then. No taking shortcuts out now. He was stuck here in this nice house with his best friend and her kids until he ate a stellar meal and had an all-around good time.

 

Toriel strode up between Chara and Frisk, and placed a delicate hand on their shoulders.

 

“Children,” she said. “This is my good friend who will be joining us for dinner. His name is Sans Skeleton.”

 

“Wassup, kids?” said Sans, on cue.

 

“Greetings. Nice to meet you, Mister Skeleton,” grinned Chara dutifully.

 

“Hello, sir,” murmured Frisk to the air.

 

“Hey now. No need for that, childrens,” Sans waved a hand. “The name’s Sans. Not Mister Skeleton. Definitely not Sir. And absolutely never _not_ The Grand Lord Of All Puns,” he winked.

 

Chara, very blatantly, did not move a facial muscle.

 

Frisk tilted her head ever so slightly.

 

Sans felt his grin stiffen involuntary.

 

Toriel planted a kiss on her kids’ foreheads.

 

“I am going to go start dinner. Be good you three.”

 

When she bustled out, with the bustle only mothers have figured out how to achieve, Chara’s gaze on Sans intensified.

 

“Alright, ‘Sans,’” he said, “Shall we just skip to the point? We all know that mom wants us to be friendly. To, ‘bond.’ So let’s just get the awkward part done with and move on to when we sit around in companionable silence until dinner, yeah?”

 

A rule follower, eh? Tricky, but shouldn’t be a problem. Sans knew how to talk to all types.

 

“That’s cool with me. I respect your dedication to the doing of the bare minimum. I got tons of ice breakers, though, if you’re interested,” said Sans.

 

“No. Thank you,” said Chara, smile unfaltering.

 

“Sure thing, bud. I know how to _pick_ my _ice_ battles.”

 

“ _Finally_ , someone _gets_ it,” said Chara, to the world at large. “It’s never about whether or not you must become friends, is it? Only about how jovial you appear before others. Now then, Frisk. This whole, ‘being of friends.’ That is, quite handily, your sphere of expertise. Tell us, how is this process meant to follow through?”

 

Frisk was staring at Sans.

 

“Are you sure someone is getting it, Chara?” she said levelly.

 

“What? You heard what the man said.”

 

“Yes. Did you?”

 

“ _Yes_.” Chara folded his arms.

 

“Perhaps he means for you to…chill out for a second, brother?”

 

“The friendship formula, Frisk. _If you please_ ,” said Chara with fierce placidness.

 

It was very slight, hardly an inclining twitch, but Sans couldn’t pretend others called him The Grand Lord Of All Puns if he missed Frisk’s post-pun smirk.

 

“Very well, Chara. Friendship is predominately established and maintained through commonalities between both parties. The more universal of these bonds include: similar hobbies, a shared ardor of a certain person, or an inclusive sense of humor. However, failing those requirements, it is widely agreed upon by doctors of friendship that a respectful facsimile can be constructed by way of simply having a pleasant and amiable demeanor.”

 

“Perfect!” said Chara, who still had not stopped smiling. “If that’s all it takes to pretend to be friends with someone, then we’ll have mom appeased in no time flat. And we all like mom already, don’t we? Ha! Everything is so much easier when you already know how things are supposed to go. Sans. Hobbies. What is it you like to do?”

 

“Welp. That’s a tough question. See, I really don’t like doing anything.”

 

“The world is a rather _dull_ place, isn’t it?”

 

Chara’s tone gave Sans a brief pause. Tones like that had _implications_.

 

“Let me try that again,” said Sans slowly. “It’s not like I don’t _like_ doing anything, it’s more that I don’t like _doing_ anything. Sleeping is more my roll than anything.”

 

There was a burning in Chara’s eyes. His smile all but glowed.

 

“But I’ll tell you what,” Sans continued, on the off chance he had built any camaraderie to lose. “One thing I do like to do is hang out with my brother. He’s pretty cool.”

 

Frisk’s blank face piqued up, and Sans noticed the loosened grip on her cane.

 

“Oh, I like hanging out with my brother, too. Chara’s the prettiest cool of all brothers. Tell me he doesn’t have the prettiest aura you’ve ever felt.”

 

Sans laughed. He was already liking this one way more.

 

Chara, in accordance with the rules of siblings under embarrassment, stuck out his tongue and made a guttural noise, not unlike the sort that would be made by an unamused cat.

 

“Stop. Both of you. Can’t you see I’m trying to get us through this with as little effort as possible?” He sniffed. “Sans. Do you like video games?”

 

“They’re alright,” said Sans, a man who had not played a video game since you could count the number of bits they had on a spider’s fingers.

 

“Great. Amazing. Fantastic. That’s what we’re doing for the next however long,” deadpanned Chara through his smirk, then took Frisk’s free hand and tugged on it…gently?

 

Huh. Well ain’t that something.

 

 “Come on. We’re going to the living room. That’s where the video games live. And die.”

 

\-----

 

Somewhere around twenty minutes later found Frisk huddled in the corner of a couch, silently running her fingers across a book, Chara mirthfully grinning at annihilating Sans’s virtual buttocks, and Sans impassively damning Chara’s existence for every loss he stared at.

 

A video game Sans had never heard of had been placed before him, and he played it on a controller he had no idea how to hold. It was some variety of ‘camera behind the person shoot-bang’ video game. When he had been prompted to select a character, Sans chose a ‘sniper’ class, because it sounded like it involved a lot of laying down, and it was important to play as a character you could identify with.

 

Sans hoped Chara would get frustrated with executing a digital assemblages of polygons and code not fighting back, proceed to call Sans out on making the game too boring, and then they could start an actual dialog from there. No such luck. If anything, the kid’s simper only seemed to thicken the more the red pixels ran. Frankly, it was starting to give Sans an eyeache.

 

This situation was exactly the second reason Sans hadn’t wanted to come.

 

It was during the lull of a loading screen when Frisk said to her book:

 

“Excuse me, Sans. Um. I was wondering what you do for a living?”

 

Sans turned to her, eager to interact less with Chara, and said: “Actually, I have two jobs. Yep, I’m one of the fortunate who gets paid to do what they love for a living. It took a long time and a lot of other careers in the meantime, but, finally, I am able to live out everyone’s dream of, not only owning my own hot dog cart, but also being able to legally sell legal hot dogs from it. And to think, they said my doctorate in applied theoretical quantum physics wouldn’t get me anywhere.”

 

“That’s not a dream,” said Chara, absolute authority on other people’s dreams, as he riddled Sans’s game avatar with bullets. “Dreams have to be spectacular. Something like blowing up the universe. That’s _my_ dream.”

 

“But that’s the job I do because I love it,” sand Sans, looking directly at Frisk. “I’m a federal judge on the weekends. Helps pay the bills, you know? But I try to keep that on the down-low. I’ve got my street cred to think about, and I figure the last thing my customers want is me judging them.”

 

“A judge? Really?” said Chara, with a worrying amount of interest. “How many people have you sentenced to death?”

 

Frisk shifted abjectly.

 

Sans heard his video game character get stabbed in the chest.

 

He stared down at Chara and said in the friendliest voice he cared to put effort into:

 

“None. The few cases I do preside over never involve something as laudable _capital_ punishment, or the risk of it. I tend to stick to the _lower cases_.”

 

Then an odd sound ebbed around the edges of his hearing. It wasn’t until Chara cocked his head to stare at something beyond Sans did he realize that the sound was not, as he originally suspected, a kitten with hiccups. Frisk was giggling.

 

“Although,” Sans went on, pressing this advantage. “There was this one time I presided over a case involving a surfer. He was a rough one. I had to make him _wave_ his rights to silence.”

 

“Is that so? What was he guilty of?” said Chara tonelessly.

 

“He was brought in under charges of illegal _board_ er crossing.”

 

There was a noise like a piglet sneezing.

 

“Yep,” Sans continued breezily. “He was really making _waves_.”

 

“Sounds like…sounds like, he only…wanted to buoy his career,” wheezed Frisk.

 

Sans felt his shoulders shake under his sniggering.

 

Chara smiled expressionlessly.

 

“ _What_ _are_ _you_ –” he began, only to be cut off by Toriel’s voice echoing down the halls.

 

“Chara! Can you be a darling child and help me in the kitchen!”

 

The boy’s eyes were a maelstrom of blood.

 

“Well. I must be off. You heard mom, I’m certain. I will talk to you soon,” he stood up and nodded to each of them: “Frisk. _Comedian_.”

 

Chara primly stalked away.

 

Frisk and Sans took a couple deep breaths to recollect themselves through the hiss of laughter.

 

“Chara helps mom all the time with cooking,” Frisk offered, at last, as Sans put down his controller. “He’s really good with knives.”

 

“Well that’s _knife_ of him. Not really surprising, though. He seems like he’s got a _cutting_ personality,” said Sans, beginning to relax. That was important to what he was going to say next. People tend to not take slights to their loved ones as seriously if they are said jocular enough.

 

“You don’t have to tell me,” Frisk closed her book and set it beside her. “He always gets the point quickly. Even if he can be a little dull at times.”

 

“He seems pretty _stab_ le aside from that,” said Sans merrily.

 

A certain atmospheric stillness grew out of these words. Except Chara’s video game, which somehow gained volume. Frisk straightened her back.

 

Well, he’s had worst reactions, at any rate. Sans leaned in.

 

“Look. I know you can see it. You’re smart. I’ve presided over cases with defendants that are every bit as kaput as he is, and they’re not in for loitering, I’ll tell ya that for free. And they always get their start early. If he keeps acting the way he’s been acting with me–”

 

“I know Chara comes off as having a bit of an edge,” said Frisk gravely. “But that’s only because he doesn’t know you. Give him a little time, that’s all. Wait until the end before you judge him, okay? He’s not all bad; really. He just…he sees things and people a little bit differently than most, is all.”

 

“Yeah? Different how?”

 

Frisk gave him a tiny frown.

 

“Um…that they’re the same. But!” she added hastily, “He _can_ treat people like people. I know he can. He’s been treating me like one for forever, and he’s just started warming up to Toriel. He hasn’t even contrived any plots to kill her for her insurance money for at least two weeks!”

 

“Sorry. Say again? _Plots to kill Toriel_?”

 

“I know!” said Frisk excitedly. “Two weeks entire without a murder thought! That’s a one thousand and four-hundred percent increase on his previous record.”

 

“Neat. Hey, out of pure curiosity, do you think everybody can be good person if they just try?” said Sans.”

 

Frisk clenched her jaw. And, wow. That was a _jawline_. Sans was amazed he hadn’t noticed it until now. You could cut diamonds on a jaw like that.

 

“I don’t play many video games,” she said carefully. “You may have noticed I have a bit of a seeing issue, and besides, most of the ones Chara plays involve a little too many exploding craniums for my liking. Some I do paly, though, are RPGs. You know, a role-playing game?”

 

“Heard of ‘em.”

 

“And whenever I want to play, Chara always drops whatever he’s doing, sits down with me, and will guide me through every step and word of any video game I ask. He describes the enemies and everything! Like, how am I ever going know what an airplane obsessed with the idea of love looks like without knowing that it smells like an airport perfume counter?”

 

Sans remained in what he hoped was tactful silence.

 

“Oh! And this one time I had to practice the controls on a training dummy, and Chara could have just told me it was a cute dummy, but he made up a rhyme about how cute it was! I heard him practicing it in the bathroom a week before I even started playing it.” Frisk said this demandingly, as if daring Sans to explain how someone who made up a rhyme about a fictional dummy could be considered irremediable in the slightest. It was, admittedly, an advance he had no defense for.

 

Chara may have all the tenderness of a rusted butcher knife, but Sans was willing to believe the possibility the kid was just a little unhappy with the world-

 

_It’s never about whether or not you must become friends, is it? Only about how jovial you appear before others._

 

-yeah, just as readily as he could believe creatures like Chara were fantastic at Playing Pretend. He was well aware that this juxtaposition was not fair, because he already knew which of those statements was factual, and knowing something and believing it to be true were far from the same thing. Belief counted for surprisingly little when your trusted friend had a knife through your ribcage, even though you knew they would never do such a thing.

 

Sans wasn’t Papyrus, who probably _would_ still believe in someone…who would…

 

…Papyrus, who made up for what Sans wasn’t, and then some.

 

Come to think of it, hadn’t Sans dreamed this or something? Siblings defending each other seemed startlingly familiar all of a sudden.

 

What Papyrus would have done here?

 

Oh, that’s right. He would believe, with extreme tolerance.

 

“Well, who knows, right?” said Sans tentatively. “Could be all he needs is some good food, some bad laughs, some nice friends…”

 

Frisk released a breath and nodded. She was smiling.

 

“A family,” she said. “And someone who can tell him no. Seriously, I don’t know what Chara would do if he got his way all the time.”

 

Then she reclined back and threw her hands towards the ceiling. “I have honestly lost count of how many times I’ve told him: ‘No, Chara, you cannot have chocolate for breakfast, lunch, _and_ dinner.’ ‘Chara, you should probably cook those noodles before you eat them.’ ‘Yes, Chara, that baby’s crying is annoying.’ ‘No, Chara, you cannot stab it with a fork to make it stop.’ ‘No, Chara, and not a spoon either.’”

 

A dark part of Sans’s mind, one he felt glow Blue on occasion, wondered what Chara would do when Frisk stopped providing a challenge, halted holding his interest, ceased to be entertaining. He opted, instead of wondering that, for a masterful subject change.

 

“But enough about him. What about you?”

 

The change could only be described as astronomical, for that was how large the room suddenly felt, despite how every part of Frisk shrunk into her striped sweater.

 

“Me?” she squeaked from the folds of wool. “Well, I’m, um, afraid there’s not much to say. I’m just a silly blind girl who talks too much. I don’t have much of a personality. That’s, erm, Chara’s job.”

 

Normally, Sans would have grinned broadly here. He still did, but put actual, real effort into carrying it on his voice.

 

“Wow,” he said. “You sure Tori’s not your biological mom? You two are way similar.”

 

Frisk withdrew further into her woolen shell.

 

“I’m not gonna force you to talk if don’t want to,” said Sans softly. “But will you let me tell you a story?”

 

Frisk cracked open an eye. It was red, like newly fallen leaves. Sans trusted that was a go-ahead.

 

“My brother, Papyrus, he’s basically the coolest guy in every existence, right? Except he can be a little lost on how to make friends sometimes. Once, when he was still in grade school, he infallibly reasoned that the best way to go about finding great friends, like I know he is, was to simply ask people if they were great friends, on the assumption that a great friend was honest. You can probably figure out what happened. The only ones that said they were great friends were the ones who took Papyrus’s lunch money and made him do their homework for six months before I found out. They stopped pretty soon after that. Point is, Frisk, is that while honesty is a virtue, Papyrus didn’t find any truly great friends with his method because the truly great people were humble. Think about that.”

 

After a silence, Frisk poked her head out of her sweater.

 

“What about you?” she said.

 

“Hm? About me? Oh, you know how it goes. All I am is a dude who loves doing nothing and has a passion for bad jokes. Not much to say, I’m afraid.” He winked, out of sheer habit.

 

“You like mom, don’t you?”

 

“Sure I do,” said Sans. “Wouldn’t be here if I didn’t. Seriously, I have no idea how she always gets me to do stuff. You think I would’ve even bothered to give you that entire waring about Chara if I didn’t _really_ care about her? I’ve told her my worst jokes, the kind you wouldn’t tell in polite company. We’re talking some Why Did The Chicken Cross The Road levels of bad. But the way you said that. That was a sentence with some velocity behind it. Almost like you said it before you could realize it was a stupid thing to say. I don’t think you’re asking if I like your mom.”

 

Frisk wore the expression of one wanting it known they were not backing down in the face of a hurriedly said question.

 

“What I think you’re asking is if I _like_ like your mom.” Sans smiled. For whose benefit he was unsure. “You know, that question is kinda the main reason why I didn’t want to come in the first place.”

 

She held her breath.

 

“The answer’s no.”

 

There was a degree of deflation in the girl’s posture. Just as Sans feared: he hadn’t answered correctly.

 

By way of explanation he said, “I’d be lying if I said the thought of the _like_ like never crossed my mind. Maybe I do actually think that, and I’m not good enough at feelings to see it. And I’ll admit feeling something like that might even be…nice. But bad times are coming, kiddo. It’s not going to pay to be a regular human around here soon. I know you may not understand it, but there’s too much that stands to be lost…undone… _reset_ , even, if I said, ‘Yes, I do.’ You need your mom, and whatever happiness you can get, more than either of us need each other. Everyone, you, me, Tori, definitely Chara, will be happier in the long haul if Tori and I stayed friends,” in his head.

 

What Sans said with his mouth was: “I dunno. It sounds like _a lot_ of work, being in a relationship, and all that jazzercise.”

 

The look Frisk gave him was indescribable without the use of the words ‘unsatisfied’ and ‘really?!’ somewhere along the line.

 

“Frisk! Sans! Dinner is ready! I advise you to come quickly before Chara eats it all!” yelled Toriel’s voice from down the hall, followed by Chara’s:

 

“Don’t think I won’t!”

 

Frisk flashed Sans a smile as she gripped her cane and slid off the couch. It said, ‘we are not finished here, Skeleton, you lazybones.’

 

“Shall we be off, sir?” she said, extending an open hand to the space above Sans.

 

He stared at it before gingerly taking it, coughing politely, and lowering it to waist level.

 

“I’m, uh, not that much taller than you, actually, madam,” said Sans.

 

“I was wondering about that,” said Frisk, thoughtfully resting her cane on her shoulder as they walked out. “Your voice isn’t where I expected it to be at all. You really don’t sell yourself short.”

 

And that was the hardest Sans laughed since he could remember.

**Author's Note:**

> If you liked what you read, please consider commissioning me to write for you, it'll help me out a lot!: http://clockworksampi.tumblr.com/post/146010687102/sampis-commission-information
> 
> Blind Frisk inspired by: ennji-undertale.tumblr.com
> 
> The hidden twist AU is that this takes place in an urban fantasy setting where Toriel, disgusted by the King of Magic, Asgore, and him waging a cold war on non-magical humans from the shadows, abdicates the throne, goes into hiding amongst normal humans, and adopts two very special humans to keep Asgore away from them. Sans is an old friend who she asked to try and keep regular humans protected from the largely magic-controlled legal system and streets as best as he can.


End file.
